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Table 1 f(α) and g(α) kinetic functions corresponding to the most widely employed kinetic models

From: Clarifications regarding the use of model-fitting methods of kinetic analysis for determining the activation energy from a single non-isothermal curve

Mechanism

Symbol

f(α)

f(α)

Phase boundary controlled reaction (contracting area)

R2

2(1 − α)1/2

2[1 − (1 − α)1/2]

Phase boundary controlled reaction (contracting volume)

R3

3(1 − α)2/3

3[1 − (1 − α)2/3]

First order kinetics or Random nucleation followed by an instantaneous growth of nuclei. (Avrami-Erofeev eqn. n =1)

F1

(1 − α)

− ln(1 − α)

Random nucleation and growth of nuclei through different nucleation and nucleus growth models. (Avrami-Erofeev eqn ≠1.)

An

n(1 − α) [−ln(1 − α)]1 − 1/n

 [−ln(1 − α)]1 − 1/n

Two-dimensional diffusion

D2

1/[−ln(1 − α)]

(1 − α)ln(1 − α) + α

Three-dimensional diffusion (Jander equation)

D3

3 1 α 2 / 3 2 1 1 α 1 / 3

[1 − (1 − α)1/3]2

Three-dimensional diffusion (Ginstling-Brounshtein equation)

D4

3 2 1 α 1 / 3 1

(1 − 2α/3) − (1 − α)2/3

Random Scission L=2 [10]

L2

2(α1/2 − α)

− 2 ln(α1/2 − 1)

Random Scission L>2 [10]

Ln

No symbolic solution

No symbolic solution